1. Field of the Invention
The present invention relates to a recording medium and a recording method which can realize an image having excellent storage stability. More particularly, the present invention relates to an ink jet recording method which can realize an image having excellent storage stability and a recording medium suitable for the ink jet recording method.
2. Background Art
In an ink jet recording process, small droplets of an ink are ejected through various mechanisms and deposited on a recording medium to form ink dots. The ink jet recording process has advantages such as emission of no significant noise, high-speed printing, and ease of full color printing.
The storage stability of prints is an important property also for the ink jet recording method. A dye which is an organic material is generally used as a colorant in an ink composition for the ink jet recording method. Therefore, exposure of the dye to ultraviolet light or a highly active gas causes a possibility that the dye is decomposed resulting in a change in color tone. On the other hand, a recording medium carrying silica is used in the ink jet recording method. The silica has high specific surface area with a catalytic activity which may catalyze the oxidation of the dye.
Several methods for improving the storage stability of an image have been proposed. For example, Japanese Patent Laid-Open No. 87989/1982 discloses that the addition of a metal oxide, a metal chloride, or tannic acid to a recording layer results in improved light fastness in storage. Further, the addition of materials considered to be an antioxidant to a recording layer has been proposed. For example, Japanese Patent Laid-Open No. 61887/1986 discloses the addition of a polyallylamine derivative, Japanese Patent Laid-Open No. 146591/1986 discloses the addition of a hindered amine compound, Japanese Patent Laid-Open No. 154989/1986 discloses the addition of a hydrazide compound, and Japanese Patent Laid-Open No. 163886/1986 discloses the addition of a thiourea derivative, a thiosemicarbazide derivative, and a thiocarbohydrazide derivative.
On the other hand, some dyes have poor storage stability. In particular, dyes which, even when placed in an environment not directly exposed to light, undergo discoloration with the elapse of time are known in the art. Such dyes are considered to be decomposed by an oxidizing gas present in the air, for example, ozone.